Rhubarb and strawberry pie

Ingredients

• Rich shortcrust pastry
• 225 gram standard flour
• pinch salt
• 1 tablespoon caster sugar
• 170 gram unsalted butter, firm but pliable, cubed
• 1 egg yolk
• 4 tablespoon chilled water
• Strawberry and rhubarb filling
• 500 gram rhubarb, washed, dried and cut into short lengths
• 1 1/2 punnets (325g) strawberries, hulled
• 1/2 cup caster sugar
• finely grated zest ½ orange
• 2 tablespoon cornflour, levelled
• 1 egg white, lightly beaten
• 1 tablespoon granulated sugar, to sprinkle
• ice cream or cream, to serve